The first BBS's I logged onto were at 300 baud, and were Commodore 64 based, generally running C-Net. Wonderful stuff.
Later went on to regularly use BBS's running many different packages on many different platforms. The most common was WWIV, but Telegard, WildCAT, Opus, (I think often referred to mistakenly as "FidoNET" which I think is an inter-BBS message transport system, but I could be wrong.), PCBoard (often called PCBoring), Renegade, Synchronet were all widely used. I ran the only PowerBBS system I knew of in the area. It was a native Windows application. (and not a very good one!);)
I ran across this list: http://bbslist.textfiles.com/ Perusing around the area code I lived in back then brings back tons of memories. So many sysops that I knew, including several that are no longer among the living, a few friends, even a few lovers. It's good to see some of their names haven't been forgotten! There's a few there that might be best off forgotten, too!;)
Time to share this article to a few of them!

If the information is available to the cloud provider to do so, then they should.... however... the cloud customer should be encrypting the data in a fashion where the cloud provider has no access, so the cloud provider then just hands over a big lump of encrypted data... then they are not in violation of anything, and are not "interfering with an investigation" etc.., but they also haven't compromised their customer's security... because they aren't capable.

Amassing such a huge fortune based on absolutely shite products but excellent marketing isn't impressive.
If he wants to impress me, he needs to give away about 77.9 billion of that, funding things like the elimination of daesh/isis/isil, al-queda & boko haram, making an excellent education free and safe across the entire surface of the earth, ensuring no-one goes hungry, and getting things like an amendment to the constitution to reverse the Citizens United decision.
When he reduces his wealth so that he here merely has enough for he and his family to live comfortably on for the next 7 generations, MAYBE I'll stop considering him a worthless piece of shit.

I think the closest thing you'll get to "out of the box" for what you're looking for is Apache Cloudstack running on Citrix XenServer for a hypervisor.
With basic networking, you can keep things pretty simple. With advanced networking, you can allow your users to build virtual data centres.
It can be 100% free open-source software as well, although if you get Citrix CloudPlatform, you get a couple of extra features, and support, but you pay for the support.
You could be something similar with other products, but CloudStack actually has a pretty amazing amount of stuff that is just there already, and doesn't need configuring.

That's about 1% of the unemployed people here in Ireland in one fell swoop. This is a big win for the Irish economy!:)
Many of those people will need training, and the knock-on effects will be massive!
It's also jobs for folks who are outside of Dublin. That plant is out in Leixlip.

You could use CEPH to do the distribution, then RADOS to create an RBD (Rados Block Device) and when you mount the RBD as asn iSCSI device, you could then build a cryptfs device on top of it, so the provider of the RBD couldn't read/write the data without the keys stored on your server (or wherever you keep them.)
The difficulty is getting something like this that is product-ized, so that a provider can give enough economy-of-scale to make it really worthwhile.